There is a known technology for displaying video provided by a rear camera that images a rear surrounding area of a vehicle and displaying video provided by side cameras that image side surrounding areas of the vehicle, instead of a rearview mirror for checking a rear side of the vehicle, a left side mirror, and a right side mirror (for example, see Japanese Laid-open Patent Publication No. 2015-009646).
Incidentally, a blind spot exists in a side mirror of a vehicle due to a reflection of the vehicle in the mirror. Even in a case where the side camera are used instead of the right and left side mirrors, blind spots exist in the same way. Therefore, it is difficult for a driver to check following moving objects including following vehicles located in the blind spots. Thus, there is a demand for a technology capable of appropriately checking surroundings of a vehicle.